Various methods and apparatus are described for a speech recognition system. The equipment controller determines whether there is any execution task when the state of equipment switches to an energy-saving mode in which consumption power is reduced, and sets the interrupt cycle of a system timer of a real time OS that generates an interrupt for causing the CPU to awaken to be long if there is no execution task so that the CPU is caused to switch to the low power mode. Certain embodiments of the new methods provide a way of predicting the level of vulnerability of an atherosclerotic plaque to rupture or thrombus formation by assessing via fiber optic NIR spectrophotometry the status of two or more parameters associated with inflamed atherosclerotic plaque in a vessel of a living patient.